Club Amiga de Montreal - CAM/CAM_CD_1.iso/files/013.lha/Mac_View/macview.doc

Text File | 1986-11-10 | 10KB | 201 lines

              MacPaint Viewer Program
                   V1.2 - 1/8/87
                 Scott P. Evernden
            ===========================

Congratulations! You have just downloaded the best MacPaint to Amiga
utility available.  I hope that you will find many uses for this tool as
well as the paint images that it displays and can produce for use on
your Amiga and/or MacIntosh.  (MacView V1.2 requires KickStart 1.2 to
operate properly.)

What does it do?
================
MacView allows you to view a standard MacPaint picture file on your
Amiga.  You can look at the image in either of Amiga's low resolution
(320 x 200 pixels) or high resolution (640 x 400 pixels) modes.  Because
the MacIntosh utilizes square pixels, only these 2 view modes are
supported, since they result in the squarest pixels available on the
Amiga.  You can switch modes while the program is running.  MacView also
allows you to convert an Amiga (color) IFF picture into a (black &
white) MacPaint picture.

MacPaint images measure 576 x 720 pixels, so it is clearly not possible
to look at the entire MacPainting at once.  For this reason, MacView
provides 1 (in hi-res) or 2 (in lo-res) thumbing bars to allow you to
pan around in the larger MacPaint image.  This latest release of the
program also provides a hand cursor which you can use to push the
MacPaint image around.  It appears whenever the left mouse button is
pressed.

This program uses a fixed color palette of black on white to replicate
the appearance of the Mac screen.  Sorry, I provided no mechanism to
change this.

In addition, MacView provides you with the ability to "snapshot" your
current screen into an IFF paint file.  IFF paint files are used by
DeluxePaint, Aegis Images, and Graphicraft, and should be compatible
with other and future Amiga paint programs.  Once you have produced the
IFF file(s), you can leave MacView, start up your favorite paint
program, and load the image.  At this point, you will have available the
full range of your paint program's capabilities to alter the picture.
Nothing could be simpler!

MacView now can read and convert an Amiga IFF file into a MacPaint file.
The program uses a simple dithering technique to convert up to 5 planes
of color information into a 1 plane monochrome image.  Now you can exchange
paintings and pictures with your MacBuddies!

Finally, rev 1.2 of MacView provides you with the capability to print
either the current screen image, or the entire MacPainting.

Installing MacView
==================
Since you now clearly have de-arced the MacView files, you need do
little more than ensure (for Workbench use) that MacView (and its
associated MacView.info file) is located at the top of a floppy's
directory structure (in DF0: or DF1:, not in a sub-directory).  You will
note that I have included (in rev1.2) a new MacPainting (and its .info
file) to get you started.  You can put the MacPaint file anywhere on the
same disk.  It's a good idea to keep several MacPaint files in their own
directory (i.e., drawer).

Using MacView
=============
MacView can be run from either the Workbench or CLI.  From Workbench,
simply open the MacView icon, and you will see an empty painting.  You
will need to use the PROJECT menu to indicate a file to be opened for
viewing.  Alternatively, from the Workbench, you can open any of the
MacPaint image files, and MacView will run displaying that file's
contents.

From CLI, simply incant "MacView filename" to get a hi-res screen of the
Mac painting.  The filename is optional.  Also, from CLI, MacView will
accept a number of "switches" to control its default operation.  These
can be listed by typing "MacView ?" for the switch list.  Current (rev1.2)
switches (changed from rev1.01) support:

    MacView [-b] [-f] [-h] [-n] [mfile]

    -b: omit MacBinary header on MacPaint output.
    Normally MacView prepends a standard 128-byte header to output
    MacPaint files.  This header facilitates the file transfer to a
    MacIntosh via the "MacBinary" XMODEM protocol.

    -f: skip MacPaint filetype checks (force)
    MacView will complain if it doesn't see certain byte patterns
    indicating a valid MacPaint input file.  You can _try_ this
    switch if you are having trouble.

    -h: hi resolution screen
    Otherwise comes up in (flicker-free!) lo-res.

    -n: noncompressed IFF output
    Graphicraft uses an older noncompressed IFF file format for its
    pictures.  You need to use this switch for that program.

 mfile: MacPaint file to view


The PROJECT menu provides options to read IFF and MacPaint files for
viewing; you can also write IFF and MacPaint files suitable for use
on the Amiga and MacIntosh, respectively.  From the PROJECT menu, you
can also print the picture being viewed.  A Partial print dumps only the
current window contents to the printer, while a Full print will produce
a full-size 8 x 10 inch hardcopy of the entire MacPainting.

The VIEW MODES menu allows you to alternate between low and high resolution
on-the-fly.

General Notes
=============
When reading an IFF picture or brush, MacView will double the size of the
image if you are in the hi-res (640 x 400) viewmode and if the IFF image
is 320 x 200 or smaller.  This will result in a chunk of the IFF painting
missing on the right side if it's width is greater than 288 pixels.
Note that your current position in the MacPainting (indicated by the
thumbing bars) is used for placement of IFF pictures being read.

The dither technique employed to convert from color to black and white is
adequate, in my opinion, for most of the IFF paintings I have tried.  I
welcome any new ideas in this area.  Unfortunately, the dithering accentuates
the flicker in hi-res mode.  One-plane IFF files will convert directly into
MacPaint files with no degradation as long as the 2 colors used have
sufficient contrast to one another.

I have almost no access to a MacIntosh, so please be aware that I am
shooting a little blindly here.  A new hotspot in MacView 1.2 concerns
the production of the MacBinary file header.  My source of information
for the format is from the Jan '86 issue of MacTutor.  I think I got it
right; let me know immediately if I'm wrong.  I have tested (briefly)
moving the MacPaint output produced by this program to a MacIntosh via
MacTerminal.  The Mac has a different date format than that used by the
Amiga - I have not yet determined if I am writing the
creation/modification date correctly in the MacBinary header.

The (-f) "force" option can be used to make MacView accept MacInput
which it would otherwise refuse.  Currently MacView performs these
checks when opening a supposed MacPainting:

    128 bytes are read, otherwise a hard (non-forceable) error.
    If the 0th, 74th, and 82nd bytes are 0, and if 65-68 are "PNTG",
        then these 128 bytes are a MacPainting MacBinary header.
    If MacBinary, and 69-72 are "MPNT" or "PANT" then OK,
        and 512 bytes (of MacPaint header) are read.
    If not MacBinary, and 0-3 contain a (long) binary 2, then OK,
        and 384 more bytes (of Macpaint header) are read.
    If not OK and no -f switch, then complain, otherwise forge ahead.

The MacPaint header is ignored by MacView.  I have reason to suspect
that a binary 3 might also legally start the MacPaint header.
Information on the various Apple formats are almost impossible to
acquire, so please inform me if this looks like i'm taking the wrong
approach.

This is still an early version of this program.  I welcome and encourage
comments and criticisms in order to improve it in any way.  Most of my
testing has occurred under the CLI, so please let me know if you
experience any anomolies.  I would like to thank those folks, especially
the Amiga Zone gang on PeopleLink, who provided ideas for new features.

Other Things
============
When producing files for import into Aegis Images, you will need to name
the IFF files with a ".pic" suffix (like "woodcut.pic"), since Images
will only list and read paintings with this extension.  Also, Images
DOES NOT accept hi-res IFF at this time, so don't bother trying.  If you
use Graphicraft, then you will need to run MacView from CLI, and use the
-n switch, since Graphicraft is an older program which doesn't
understand compressed IFF files.  Graphicraft, like Images, also can't
handle hi-res pictures.

I am well aware of a number of features which would be desireable to add
to this program.  Real file requesters, color control, positive/negative
switching, etc., are just some ideas which are obvious.  Perhaps a
choice of dither patterns should be offered to yield different
graininess in the MacPaint output.  MacView does not yet support HAM IFF
images ($hould it?).  Finally, some form of contrast/brightness control
for the IFF->MacPaint conversion could be added.

These files and the MacView Program may be freely distributed and given
away as shareware, as long as you don't make any money from it and you
don't claim you're the author.  Leave this file and allow me the credit!

Lastly, I am still (still!) paying for my Amiga, and I need your help.
If you feel that this program is serving you in some useful way, then
consider sending me $10 or more.  This would serve to uplift my
confidence in shareware, and to assure you of future stuff.  If you
don't like the program, then forget it (write one yourself!).  Money and
hardcopy correspondence can be directed to me at:

    Scott P. Evernden
    9 Courtland St.
    Holliston, MA 01746

Electronically, I am:

    PLINK:    SCOTT E
    CIS:    73116,3451    (don't expect a speedy response)

Have fun!